The present disclosure relates to an inkjet recording apparatus that records on a recording medium, such as a sheet of paper, by discharging ink onto the recording medium. In particular, the present disclosure relates to a recovery mechanism for a recording head that after ink has been purged from a discharge nozzle, wipes away purged ink attached to an ink discharge surface of the recording head using a wiper.
Recording apparatuses such as facsimile machines, copiers, and printers that record an image on a recording medium such as paper or an overhead projector film can for example be classified as an inkjet type, a wire dot type, or a thermal type. Inkjet recording apparatuses can be further categorized as either a serial type in which a recording head scans over the recording medium while recording thereon or a line head type in which recording is performed by a recording head that is fixed to a body of the apparatus.
A line head inkjet recording apparatus for example includes a line inkjet head (recording head) for each of a plurality of colors. The line inkjet head has a plurality of discharge nozzles that are arranged at specific intervals along the entire width of a printing region that perpendicularly intersects a conveyance direction of the recording medium. Printing can be performed over the entire recording medium by discharging ink from discharge nozzles corresponding to printing positions in accordance with conveyance of the recording medium.
In an inkjet recording apparatus such as described above, printing ability of the recording heads may be reduced due to occurrence of poor linearity of ink (trajectory deflection) or ink discharge failure. A main cause of such problems is thought to be meniscus abnormality occurring, for example, as a result of attachment, to an ink discharge surface of the recording head, of contaminants such as paper dust or dirt generated during paper conveyance, fine ink droplets (referred to below as mist) discharged at the same time as ink droplets for image recording, or splash back mist created when the ink droplets attach to the recording medium. Also, as a result of mist attaching and drying at a capping position, sealing tightness while a nozzle is in a capped state may be reduced and consequently viscosity of ink within the nozzle may increase.
Therefore, a configuration in which a recovery process for a recording head is performed is commonly adopted in order to prevent drying of ink in ink discharge nozzles having openings in the ink discharge surface of the recording head and in order to prevent nozzle clogging due to increased viscosity of ink in the ink discharge nozzles. After ink has been purged from the nozzles, the recovery process for the recording head is performed by using a blade shaped wiper to wipe away purged ink that is attached to the ink discharge surface (nozzle surface).
In one commonly known example, wiping of an ink discharge surface of a recording head is performed by applying a wiper against a portion of the ink discharge surface in which no nozzles are present with a specific contact pressure. One example of an inkjet recording apparatus includes a wiping mechanism having two wipers that can successively be brought into contact with an ink discharge surface of a recording head. A preceding one of the wipers wipes away purged ink and a succeeding one of the wipers wipes away ink remaining in proximity to a wiping start position of the preceding wiper.